Not at all! Just like with price, the difference between zero and one is hugely more consequential than any extra dollar added. Think of it: if you see a community with no posts in the last hour, or day, it does feel a bit deserted. Or a post without comments. By adding a post, or the first comment, you can be the difference for the next guy's impression, and encourage them to do the same, and then the ball gets rolling, and that's how you get momentum.